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JAMES A. G. REHN 307 



STUDIES IN COSTA RICAN DERMAPTERA AND 
ORTHOPTERA 

BY JAMES A. G. REHN 

My interest in the Orthopterous fauna of Costa Rica extends 
back to the year 1903, when in three papers 1 were recorded the 
first collections from that country examined by me. Since that 
time much additional Costa Rican material has passed into my 
hands, many species have been recorded and numerous ones 
described, but a very large portion of these collections is as yet 
unreported. Much progress has been made in the development 
of our knowledge of the Dermaptera and Orthoptera of Mexico, 
Central America and northwestern South America, and a far 
better groundwork for resumed study is now available. 

For a number of years one of my greatest desires has been to 
prepare a comprehensive catalogue and faunistic study of 
Costa Rican Dermaptera and Orthoptera. For a tropical re- 
gion of greatly diversified conditions, the fauna of Costa Rica 
is as rich as, and, relatively speaking, probably better known 
than, that of any other country of similar size within the Amer- 
ican tropics. There exists a possibility of the realization of my 
desire in the not too distant future, and a definite amount of 
study time is now being given to the extensive collections in 
hand. These I hope to be able to supplement, before final 
publication, with additional, personally secured, material and 
observations. 

As it appears desirable to make known new forms recognized, 
and important changes or synonymy necessitated as the work 
progresses, papers under the title here given will be brought 
out from time to time. 

1 Studies in American Forficulidae. Proc. Acad. Nat. Sci. Phila., 1903, pp. 
299-312. Studies in American Blattidae. Trans. Amer. Entom. See, xxix, 
pp. 259-290. On Two Earwigs of the Genus Labia from Costa Rica. Entom. 
News, xivr, pp. 292-293. 

TRANS. AM. ENT. SOC. XLVII. 



308 COSTA UlCJAJST DERMA pteka and okthopteka 

PAPER ONE 

Two New Genera and Three New Species 
of Dermaptera 

A study of the Dermaptera material now in hand, and a corre- 
lation of all published Costa Rican records of the order, has 
been completed, and the present small contribution treats of 
the undescribed material located. One of the genera described 
as new is based on a species long known; a better acquaintance 
with its relatives makes its generic separation imperative. The 
other new genus is necessitated by the rediscovery of the geno- 
type of the genus Neolobophora. 

Labiidae 
labiinae 

Prolabia calverti new species (Plate XVII, fig 1.) 

A member of the Arachidis Group of the genus and far more 
closely related to P. triquetra Hebard, 2 from southern Mexico, 
than to the other species of the assemblage. In general form 
the present species is very similar in the male sex to triquetra, 
but the forceps, while of the same general type, have their form 
less robust, their dorsal carinae nearer the median line of the 
branches, and the proximo-internal tooth is a more rounded 
tubercle; the pygidium of the male is proportionately shorter 
and broader than in triquetra, its caudo-lateral angles are less 
pronounced, the distal margin subtruncate and the dorsal sur- 
face inflated with an evident medio-longitudinal sulcation. 
From arachidis the present species is markedly distinct, showing 
much the same differences as triquetra. The feature of pygidial 
inflation is marked and quite diagnostic. 

Type. — d 71 ; Reventazon Valley below Juan Vinas, Gosta Rica. 
Elevation, 2500 feet. May 1, 1910. (P. P. Calvert; from un- 
rolled Heliconia leaf.) [Academy of Natural Sciences of Phila- 
delphia, Type no. 5379.] 

2 Trans. Amer. Entom. Soc, xliii, p. 417, pi. xxviii, figs. 5, 6 and 7, (1917), 
[Orizaba (type locality) and Minatitlan, Vera Cruz, Mexico; Ohalchicomula, 
Puebla, Mexico]. 



JAMES A. G. REHN 309 

Size small; form moderately slender, less robust than in triquetra and much 
more slender than in arachidis; surface moderately polished with exceptions 
noted below. 

Head in outline broad pyriform, greatest width across eyes faintly less 
than greatest length of same; interantennal-interocular region with its central 
area subdeplanate; occiput with paired arcuately and transversely disposed 
impressions, 3 which are separated mesad, in contract with eyes laterad; caudo- 
lateral occipital angles well rounded, this region with a few short bristle-like 
hairs; median portion of occipital margin shallowly obtuse-angulate emargin- 
ate. Eyes little prominent, slightly longer than postocular portion of genae. 
Antennae damaged. 4 

Pronotum subquadrate, slightly transverse; cephalic margin subtruncate, 
lateral margins approximately parallel, caudal margin broadly and entirely 
arcuate, passing into the lateral margins; surface of cerjialic half of disk 
appreciably convex with a brief median sulcation cephalad, caudal section 
mesad with a subequal section reaching to caudal margin and weakly convex 
in transverse section, narrow cephalo-lateral and broad caudo-lateral portions 
subdeplanate. Tegmina as in P. triquetra, but distal margin weakly concave. 
Wings projecting distad of the tegmina somewhat less than one-half of length 
of latter, immediate apex narrowly truncate. 

Abdomen short fusiform, much as in triquetra, surface largely and obscurely 
impresso-punctulate and almost completely without hairs; abdominal keels 
as in triquetra but distal pair more pronounced; anal segment rectangulate 
transverse, greatest length nearly three times in greatest width; distal margin 
with extremely slight projections above insertion of each forceps arm, these 
projections weaker than in triquetra, mesad this margin is truncate; surface 
of anal segment appreciably declivent meso-distad and there, near margin, 
with a brief median sulcation. Pygidium subquadrate, about one and one- 
third times as wide as long, lateral margins subparallel, caudo-lateral portions 
narrowly oblique truncate, distal margin subtruncate, non-cingulate, lateral 
angles of caudal margin with brief tuberculations ; surface of pygidium mark- 
edly inflated and bullate, a deep medio-longitudinal sulcation indicated on 
proximal three-fourths. Forceps of the general type and form found in P. 
triquetra, but more slender and rather more regularly tapering, in section 
more nearly equilateral than in triquetra, as the dorsal carina instead of being 
internal in position, as in triquetra, more nearly approaches the median line 
of the arm, particularly mesad; proximo-internal tooth distinct though small, 
rounded tuberculate; internal margin distad of tooth unarmed; distal half 

3 These impressions may have been produced by shrinkage of the chitin 
in the drying of this specimen, which had been preserved in alcohol, and for 
that reason we have not given them as diagnostic features. They are 
represented in triquetra only by slight indications, and, while quite regular 
in the present specimen, we prefer to await the acquisition of further material 
before citing them as distinguishing features. It is necessary, however, to 
discuss them in the general description on account of their striking character 
and, possibly normal, occurrence in the type. 

4 These appendages were intact when first examined, both in spirits and 
dry, and the preliminary generic assignment was then made, 

TRANS. AM. ENT. SOC, XLVII. 



310 COSTA RICAN DERMAPTERA AND ORTHOPTERA 

of arms with dorsal surface less deplanate than in triquetra, dorso-external 
face more concave than in triquetra; hairiness of forceps as evident as in 
triquetra, most pronounced on external surfaces. Penultimate sternite as 
in triquetra. Limbs robust, as in triquetra, femora inflated. 

General color bone brown to clove brown on the head and pronotum, pass- 
ing to russet on the abdomen and walnut brown on the forceps. Tegmina 
evenly paling in sutural half to hazel and on humeral angle to ochraceous- 
buff, the disto-lateral section remaining dark. Exposed portion of wings 
ochraceous-buff proximad, passing toward general color distad. Dorsum 
of abdomen with an indefinite infuscation mesad, which is marked only on 
anal segment. Pygidium dull ochraceous-tawny. Limbs of the general 
color, paling in the vicinity of the articulations and on the tarsi to buffy. 

Length of body (exclusive of forceps), 6.2 mm.; length of pronotum, 1; 
greatest width of pronotum. 1.1; length of tegmen, 1.8; length of forceps, 1.9. 

The type is unique. 

It gives me great pleasure to dedicate this interesting species 
to its collector, my colleague Dr. Philip P. Calvert, as a token 
of esteem as well as appreciation of his kindly help and advice, 
often sought and here gladly acknowledged, and also in recogni- 
tion of his important contributions to our knowledge of the 
entomology of Central America. 

FORFICULIDAE 
OPISTHOCOSMITNAE 

As Hebard has already suggested, 5 we feel convinced that the 
Neolobophorinae is not sufficiently distinct from the present 
subfamily to warrant its recognition as of equal rank. We feel 
also that the Opisthocosmiinae as here understood should, in a 
linear classification, precede the Ancistrogastrinae, and come 
between the Forficulinae, and probably Eudohrninae, and the 
Ancistrogastrinae. 

The genus Neolooophora Scudder 6 has as its genotype, by 
monotypy, N. bogotensis Scudder, based on a single female from 
Bogota, Colombia. While recorded more than once by later 
authors it would seem, as elaborated below, that the species 
has remained virtually unrecognized until the present time. 

While I was engaged in the present study Mr. Hebard placed 
in my hands two remarkable male Neolobophorine specimens 

5 Trans. Amer. Entom. Soc, xlv, pp. 95-96, (1919). 
6 Proc. Boston Soc. Nat. Hist., xvn, p. 281, (1875). 



JAMES A. G. REHN 311 

from Muzo, Boyacd, Colombia. 7 These individuals possessed 
very elongate, slender, simple forceps, and were in every way 
quite different from anything seen previously. Efforts to locate 
then invariably led me to Neolobophora bogotensis, the original 
description of which was discouragingly indefinite about features 
which might have assisted in the recognition of the opposite 
sex. A call for help to Dr. Nathan Banks, at the Museum 
of Comparative Zoology, elicited some very useful notes made 
from the unique type of Scudder's bogotensis. These critical 
observations are sufficiently convincing to demonstrate that the 
Muzo insect is the previously unknown male of Scudder 's species. 
It is evident from the Muzo individuals of bogotensis that 
the erection of two new genera is necessary, one to accommodate 
the "Neolobophora" ruficeps of the literature of recent decades, 
and the other to include the insect recorded as Neolobophora 
bogotensis by Bormans from Central America. Hebard's genus 
Neocosmiella 8 is the closest relative of true Neolobophora, as 
one might expect from its geographic propinquity, but it differs 
in certain features which might be tabulated as follows: 

Neolobophora Neocosmiella 



(Male sex only known) 
Antennae with second, third and 
fourth joints together one and one- 
third times as long as proximal joint. 
Tegminal keel at humeral angle 
very marked, carinately elevated, be- 
coming obsolete at distal fourth. 

Surface of tegmina coarsely cori- 
aceo-punctate, visible to the naked 
eye. 



(On basis of male sex) 

Antennae with second, third and 
fourth joints together subequal to 
proximal joint. 

Tegminal keel at humeral angle 
distinct, but not carinately elevated, 
becoming obsolete at distal fourth. 

Surface of tegmina apparently 
smooth to the naked eye, minutely 
shagreenous under considerable 
magnification. 

These two groups are unquestionably developments from a 
common ancestor, but their features of difference appear to 
warrant generic separation. When the female sex of Neocos- 
miella is known, and the tarsal structure of the two genera is 
compared, we will be in a better position to discuss more critically 
their affinity. The unique type of Neocosmiella now lacks com- 
plete tarsi. 

7 VIII, 1921, (A. Maria), [Hebard Collection]. 

8 Trans. Amer. Entom. Soc, xlv, p. 95, (1919). 

TRANS. AM. ENT. SOC, XLVII. 



312 COSTA RICAN DERMAPTERA AND ORTHOPTERA 

RHYACOLABIS 9 new genus 

This interesting genus shares certain features with Neolob- 
ophora and others with Neocosmiella, to both of which it is 
related. From these two genera, however, it differs in the 
surface of the abdomen being hirsute, the tegminal keel complete 
and the pronotum weakly transverse. From Neolobophora, 
Rhyacolabis also can be distinguished by the tegminal keel being 
strongly developed, carinately elevated, instead of moderately 
evident and not carinately elevated, while it agrees with Neolo- 
bophora ir having the surface of the tegmina minutely ehagreen- 
ous when seen under a strong lens, and apparently smooth to 
the naked eye. From Neocosmiella the new genus readily can 
be distinguished by the tegmina having their surface as above, 
and not coarsely coriaceo-punctate, as well as in the lateral 
portions of the pronotum being broad and greatly encrouching 
upon the disk mesad, instead of narrow and subequal, as in 
Neocosmiella. 

In the absence of the male sex of Rhyacolabis it may seem 
hazardous to describe the insect as a new genus, but as the species 
on which it is founded has been figured and reported for many 
years, and the differences appear, from our knowledge of allied 
genera, to be of considerable importance, no other course is 
open. This is clearly evident when it is realized that to attempt 
to fit it in either of the other genera would do violence to their 
cohesiveness. 

Linearly arranged the genera of this assemblage, which we 
have had to examine in connection with our Costa Rican study, 
would stand as follows: Rhyacolabis, Neocosmiella, Neolobophora 
and Metresura. The genus Rhyacolabis has a facies which is 
appreciably Ancistrogastrine. The African genus Archidux 
Burr 10 is apparently a near relative of Rhyacolabis, having a 
complete humeral tegminal keel, but it has the abdomen smooth 
and the limbs elongate, while doubtless other important features 
would be found to exist on comparison. Archidux has a prono- 
tum and limb development much as in Neolobophora and Neo- 
cosmiella, while its general facies suggests Metresura, but the 
head structure alone prevents confusion with the latter genus. 

9 From pua^ volcano, and \(X$iq, forceps. 

1,1 Ann. and Mag. Nat. Hist., (8), iv, p. 124, (1909). 



JAMES A. G. REHN 313 

Generic Description. — Head short and broad, with twin im- 
pressions between eyes; occiput uninflated, sutures faint. 
Pronotum subquadrate, narrowly transverse, weakly' narrower 
than width across base of tegmina; lateral areas broad. Tegmina 
abbreviate, attingent, subobliquely truncate distad; humeral 
keel prominent, carinately elevated, continuous; surface of teg- 
mina minutely shagreenous under magnification. Wings not 
evident. Abdomen with stink glands of third tergite weakly- 
developed, those of fourth tergite strongly developed; sides of 
tergites simple; disto-dorsal tergite of female simple; subgenital 
plate of female ample; surface of abdomen and forceps with a 
thin but regularly distributed clothing of adpressed golden hairs. 

Genotype. — Rhyacolabis anachoreta new species. 

Rhyacolabis anachoreta 11 new species (Plate XVII, figures 2 and 3.) 
1893. Neolobophora bogotensis Bormans, Biol.-Cent.-Amer., Orth. i, p. 8, 

pi. ii, fig. 9. [9 ; "Volcan de Irazu, 6000-7000 feet, Costa Rica;Volcan 

de Chiriqui, 2500 to 4000 feet, Panama."] (Not Neolobophora bogotensis 
Scudder, 1875.) 
1900. Neolobophora bogotensis Bormans, Das Thierreich, xi, p. 100. [ 9 ; 

" Costa Rica am Vulkan von Irazu, in 1830-2130 m. Hohe, Panama am Vul- 

kan von Chiriqui, in 760-1200 m. Hohe."] (Not Neolobophora bogotensis 

Scudder, 1875.) 

The figure given by Bormans in the Biologia will greatly as- 
sist in the recognition of this previously misunderstood species. 
The character of the pronotum, the general form of the tegmina, 
the position and indication of their humeral keel, and the gener- 
al proportions are all shown sufficiently well to make the figure 
of real use. Although the type is a female I feel less hesitation 
about describing it than would be the case if we had no previous- 
ly published information. 

Type. — 9 ; Volcano of Irazu, Costa Rica. February 22, 1902. 
(M. Cary.) [Hebard Collection,, Type no. 782.] 

Size rather small; form broad, depressed; surface of sterna, abdominal 
tergites and sternites, subgenital plate, forceps and limbs well clothed with 
short hairs, these erect on sterna, moderately or distinctly depressed else- 
where. 

Head broad, very slightly broader across eyes than greatest length, post- 
ocular portion of head very faintly longer than eyes, latero-caudal angles 
very broadly rounded; occiput with its surface bearing a very slight deplana- 
tion rnesad, but otherwise smooth, with sutures distinctly but delicately 
indicated, and not at all impressed. 

11 A hermit — in allusion to its isolated habitat and hairy covering. 

TRANS. AM. ENT. SOC, XLVII. 



314 COSTA RICAN DERMAPTERA AND ORTHOPTERA 

Pronotum broader than long; cephalic margin truncate; latero-cephalic 
angles narrowly rounded; lateral margins subparallel, arcuato-truncate; latero- 
caudal angles rounded obtuse; caudal margin broadly arcuate. Surface of 
disk in section gently arcuate, with an impressed median sulcus in cephalic 
half, followed at caudal two-thirds by a median circular pit-like depression, 
paired circular depressions placed in middle of lateral halves of cephalic 
section of disk; mesad the disk is narrowed by extension of lateral areas, 
which widen regularly caudad to this point of greatest width, where they in- 
dividually constitute one-fifth of total pronotal width, then by a pronounced 
meso-laterad directed oblique definition, become obsolete. Lateral • areas 
very appreciably reflexed dorsad. 

Tegmina with greatest length equal to one and one-fourth times greatest 
length of pronotum, seen from dorsum the pair slightly and regularly broaden 
caudad, except in distal fourth, where the humeral carinae are subparallel 
when tegmina are in normal position; sutural margins in contact for greater 
portion of their length, exposing scutellum proximad; distal margin truncate, 
but little oblique, nearly transverse; humeral keel carinate, elevated, pro- 
nounced, continuous; costal margin straight for proximal two-thirds, in 
distal third arcuate to keel; marginal field with width equal to slightly more 
than one-fourth of length of same. 

Abdomen broad, short fusiform. Disto-dorsal tergite rather small,, sym- 
metrically trapezoidal; surface moderately depressed meso-distad. Sub- 
genital plate very ample, scoop-shaped, its free margin broadly arcuate 
with faint median flattening. Forceps simple, tapering, tips moderately 
hooked and weakly recurved, internal margin serrulate; surfaces striatulate, 
particularly along dorso-internal section. 

Limbs largely damaged or missing. Cephalic limbs short and robust. 

General color deep bay on the dorsum of abdomen, becoming dresden 
brown to auburn on venter, tegmina, disk of pronotum and head, latter pale 
on occiput. Lateral areas of pronotum pale chamois. Forceps pale ochra- 
ceous-tawny. Remaining limbs ochraceous-buff. 

Length of body (exclusive of forceps) 8 mm.; length of pronotum, 1.35; 
greatest width of pronotum 1.6; length of tegmen, 1.68; greatest width of 
tegmen, 1.09; length of forceps, 2.25. 

In addition to the type we have before us an immature speci- 
men of small size, bearing the same data. 

METRESURA 12 new genus 

From Neolobophora and Rhyacolabis this genus is readily 
distinguishable by the inflated and divided occiput, the small 
eyes and the tegmina being without true humeral keels. As 
is the case with Neolobophora, Metresura also differs from Rhy- 
acolabis in the broad disk and narrow lateral sections of the 

12 From usTpTQdtc measuring and oupa tail, in allusion to the divider-like 
forceps of the male. 



JAMES A. G. REHN 315 

pronotum, the non-hirsute abdomen and elongate and slender 
limbs. From Neocosmiella Hebard the new genus differs in 
the inflated and divided occiput, small eyes, and in the absence 
of true tegminal keels, while the male forceps also lack the 
prominent tooth found at the proximo-lateral base in Neo- 
cosmiella. 

Generic Description. — Head broad cordiform; occipital sutures 
distinct, occiput weakly or distinctly bullate; postocular portion 
of head longer than eyes. Pronotum subquadrate, lateral mar- 
gins subparallel; latero-cephalic angles rectangulate, at most 
but narrowly rounded; caudal margin moderately arcuate; disk 
of pronotum broad, weakly arcuate transversely; median sulcus 
distinct cephalad; lateral ascending sections very narrow. Teg- 
mina brief, little longer than pronotum; distal margin obliquely 
concavo-truncate; juncture of horizontal dorsal and vertical 
lateral sections of tegmina without true keel. Wings not evident. 
Abdomen with third and fourth tergites with well-developed 
lateral folds, that on fourth larger; surface of abdomen punctulate, 
polished. Forceps of male slender, elongate, not contiguous at 
the base, with at least one tooth near median section, apices 
incurved. Forceps of female simple, attenuate, apices narrowly 
incurved. Pygidium of male distad simple or bispinose. Limbs 
elongate. 

Genotype. — Metresura ruficeps (Burmeister) [Forficula rufi- 
ceps]. 

In addition to the genotype, Metresura contains at least two 
species which have been referred to Neolobophora, and which 
should be removed from the latter — borellii Burr and insolita 
Borelli. Of the former material is now before us, 13 and the 
latter is clearly a member of the same generic unit. Several 
other species have been referred to Neolobophora which we have 
not been able to examine. The African genus Archidux Burr 
shows distinct relationship to Metresura on one hand and the 
restricted Neolobophora complex on the other. From Metresura, 
however, it can be distinguished by the non-impressed head su- 
tures and uninflated occiput, as well as the possession of com- 
plete and apparently well indicated humeral tegminal keels. 
Burr 's borellii has the occipital inflation less marked than in rufi- 
ceps, and the tegmina are more sharply folded proximad at the 

13 See Hebard, Trans. Amer. Entom. Soc, xltii, pp. 425-526, (1917). 

TRANS. AM. ENT. SOC, XLVII. 



316 COSTA RICAN DERMAPTERA AND ORTHOPTERA 

humeral angle than in the latter species, but there can be no 
confusion with the very smooth head and completely keeled 
tegmina of Neolobophora. 

ANCISTROGASTRINAE 
Paracosmia carrikeri new species (Plate XVII, figures 4, 5 and 6.) 

A striking member of the genus, more nearly related to P. 
gulosa (Scudder) and silvestrii Borelli than to the other species 
which have been referred to the genus. From gulosa, with a 
male paratype of which the new form has been compared, 14 
carrikeri is seen to differ chiefly in its more elongate, attenuate 
form; in the head being more elongate cordiform; the pronotum 
proportionately narrower, being appreciably narrower than the 
head, and the lateral margins nearly straight, faintly convergent 
caudad; the abdomen elongate fusiform; in the fifth and sixth 
dorsal abdominal segments being without lateral carinae; in the 
ultimate dorsal abdominal segment having the lateral margins 
weakly convergent caudad, instead of subparallel; in the more 
elongate and distad attenuate forceps, which are straighter in 
profile, with the apices more falcate and without as marked a 
predistal"bite"as found in gulosa; in the angulate emargination 
instead of truncate median emargination of the penultimate 
ventral abdominal segment, and in the elongate, attenuate limbs. 
From silvestrii Borelli the new form differs in the same features 
as from gulosa, except that the ultimate dorsal abdominal seg- 
ment agrees in shape in silvestrii and carrikeri, and in silvestrii 
the tegmina are short and the wings not evident, while in carri- 
keri these are as in gulosa. Hebard 15 already has suggested that 
gulosa and silvestrii may represent forms of the same species, 
which appear to us to be quite probable. 

No comparison is necessary with the other species which have 
been referred to Paracosmia, or any species which have been 
assigned to related genera. 

Type.— &; Turrialba, Costa Ilica. (M. A. Carriker, Jr.) 
[Hebard Collection, Type no. 212.] 

Size moderately large; form subdepressed; surface smooth but dull. 
Head subelongate cordiform, slightly longer than broad, width across eyes 
faintly greater than caudad of same; caudo-lateral angles broadly rounded; 

14 See Hebard, Trans. Amer. Entom. Soc, xliu p. 428, (1917). 

15 Vide supra. 



JAMES A. G. REHN 317 

occipital margin very slightly and broadly emarginate; sutures distinctly 
but shallowly marked; proximal antennal joint conico-cylindrical, greatly 
elongate, one and one-half times as long as greatest length of eye; second 
joint minute; third joint not quite half length of first; remainder missing. 

Pronotum with length subequal to width, latter less .than that of head; 
cephalic margin slightly oblique-truncate laterad, latero-cephalic angles 
narrowly rounded, lateral margins faintly arcuate, faintly converging caudad, 
broadly rounding into the caudal margin, which is well arcuate with the 
faintest possible median angle; disk of prozona considerably elevated, with a dis- 
tinct medio-longitudinal sulcus, laterad of which is placed on each side a 
single impressed puncture; metazona depressed, with a slight but distinct 
median carina, lateral portions considerably reflexed dorsad. 

Tegmina twice as long as pronotum, broad, their combined width almost 
twice that of pronotum; latero-cephalic angles very well rounded, when viewed 
from dorsum the lateral margins are seen to be slightly converging caudad; 
tegmina carinate throughout their length; caudal margin slightly oblique, 
weakly concave. Wings with exposed portion slightly shorter than length 
of pronotum, arcuate laterad, their apices squarely truncate. 

Abdomen subfusiform in outline; third and fourth segments bearing dis- 
tinct lateral plicae, those of fourth segment the larger; laterad the dorsal 
segments have their caudal margins weakly angulate produced caudad, 
these non-carinate. Penultimate dorsal abdominal segment subrectangulate, 
transverse, greatest length contained one and one-half times in its greatest 
width, lateral margins slightly converging caudad; surface of segment with 
a faint median sulcus succeeded caudad by a small median pit near the caudal 
margin, latter very slightly but broadly arcuate between the bases of the 
forceps; lateral angles of penultimate dorsal abdominal segment well recurved 
beneath the forceps, with two spines of which the caudal (and also apical) 
one is the larger. Forceps moderately elongate, enclosing an elongate pyri- 
form area, the arms distinctly but not greatly depressed; base on internal 
side with a large blunt shoulder-like projection, thence moderately arcuate 
and converging to the considerably recurved and falciform tips; no teeth 
present but internal margin crenulate for almost its entire length, the pre- 
apical angle found in many Ancistrogastrine forms being represented by an 
obtuse angle. Penultimate ventral abdominal segment broadly obtuse- 
angulate emarginate, with lateral angles produced into short acute projections, 
lateral margins of the segment converging caudad, the whole plate decidedly 
transverse. Limbs elongate and very slender; caudal metatarsus slightly 
exceeding the third tarsal joint in length. 

General color bay, the tegmina and exposed portion of the wings largely 
Vandyke brown. Head, aside from the labrum, clypeus and eyes, burnt 
sienna; clypeus Vandyke brown and labrum marked with same; eyes seal 
brown; two proximal antennal joints seal brown, the third tawny-olive. 
Pronotum vandyke brown mesad, bordered laterad on the prozona with clear 
chestnut, the whole broadly margined laterad with clear ochraceous. Teg- 
mina with a poorly defined premedian spot and a wash at the latero-cephalic 

TRANS. AM. ENT. SOC, XLVII. 



318 COSTA RICAN DERMAPTERA AND ORTHOPTERA 

angle, ochraceous-rufous. Forceps similar to the abdomen in color. Femora 
with proximal portion distinctly ochraeeous, the remainder seal brown; 
tibiae ferruginous. 

Length of body (exclusive of forceps), 13.3 mm.; length of pronotum, 1.8; 
greatest width of pronotum, 1.9; length of tegmen, 3.6; length of forceps, 5.8. 

The type of this most interesting species is unique. It is 
with the greatest of pleasure that we dedicate this species to 
its collector, M. A. Carriker, Jr., a friend of many years, a 
most genial and delightful companion, and a splendid naturalist 
in the field and in the laboratory. 



Explanation of Plate XVII 

Fig. 1. — Prolabia calverti new species. Dorsal view of forceps and pygidium 

of male {type). (Greatly enlarged.) 
Fig. 2. — Rhyacolabis anachoreta new genus and species. Dorsal outline of 

head, pronotum and tegmina of female (type). (X 9) 
Fig. 3. — Rhyacolabis anachoreta new genus and species. Lateral outline of 

tegmen of female {type). (X 9) 
Fig. 4. — Paracosmia carrikeri new species. Dorsal view of male (type). 

(X3) 
Fig. 5. — Paracosmia carrikeri new species. Outline of venter of apex of 

abdomen, with base of forceps, of male (type). (X 6) 
Fig. 6. — Paracosmia carrikeri new species. Outline of lateral aspect of apex 

of abdomen, with base of forceps, of male (type). (X 6) 



Trans. Am. Ent. Soc , Vol. XLVII. 



PI. XVII. 








REHN— COSTA RICAN DERMAPTERA